Relevance. The intensin’s microbiota plays a crucial role in feed digestion and nutrient digestion in farm poultry, influencing zootechnical performance.The aim of the study was to compare the effect of the addition of lysine and methionine in various forms to the diet on the composition of the intestinal microflora of chickens and roosters of the «Smena 9» cross, as well as to establish a connection between the composition of microflora in different diets with the zootechnical indicators of birds.Methods. Physiological reseach were carried out on meat chickens of the Plimutrock breed and roosters of the Cornish breed of the parent herd of the domestic cross “Smena 9” selection of the “Smena” SSC. 4 groups were formed (control 1A and experimental 2A-4A) such as of 9 laying heads and 4 groups of 9 rooster heads (control 1B and experimental 2B-4B). Analysis of samples of the contents of blind processes of the intestine of birds was carried out by PCR.Results. As shown by the quantitative PCR method, the studied feeding factors: various sources of lysine and methionine and a 5% reduced level of metabolic energy of feed had a different effect on the composition of the microflora of chickens and roosters of the parent stock of the new cross «Smena 9». For example, with a decrease in the level of metabolic energy in the diets of chickens, there was a decrease from 1.2 to 5.0 times in such representatives of the normoflora as Bacteroidetes and Eubacteriaceae, compared with similar groups with a basic amount of metabolic energy (p < 0.05). When lysine was introduced into the diet in the form of monochlorohydrate and DL-methionine, a decrease in the weight of ovaries with an oviduct by 6.9 g was noted against the background of a decrease in the level of metabolic energy compared with the corresponding group with a base content of metabolic energy (p ≤ 0.05), whereas when using lysine in the form of sulfate and methionine in the form of a hydroxyanalog of methionine, a similar effect was reduced not noted (p > 0.05). At the same time, shifts in the composition of microflora against the background of changes in diets did not have any connection with the studied zootechnical parameters in chickens and roosters.